1. Field of the Invention
The invention relates to the field of topical treatments for topical viral infections, especially herpes simplex infections and warts.
2. Description of Related Art
The herpes simplex virus (HSV) is a common cause of infections of the skin and mucous membranes, and may also cause more serious infections in other parts of the body. There are two distinct types of the virus, HSV-1 which usually infects the oral cavity and which is not sexually transmitted, and HSV-2, which is known as genital herpes and which is sexually transmitted. Both types of the virus, may however, be found at any area of the body.
HSV infections have become extremely widespread; it is estimated that about 20% of Americans will have a positive blood test for HSV-2.
Other types of the herpes virus are responsible for other infection, with herpes zoster being responsible for chicken pox and human herpesvirus 8 thought to be responsible for Kaposi""s sarcoma.
When HSV enters the human body, it penetrates vulnerable cells in the lower layers of the skin, and attempts to replicate itself in the cell nuclei, thereby destroying the cells and causing the blisters and inflammation characteristic of the infection. The resulting skin lesions are often tiny blisters grouped together on an inflamed base. Viral particles are carried from the skin through branches of nerve cells to clusters at nerve cell ends called ganglia. The HSV in the ganglia enters an inactive or latent state in which replication does not occur but in which the virus survives. While infection is not evident during the latent period, but the virus may begin to multiply again, causing symptoms. With HSV-1, there is recurrence of infection in 20 to 40% of cases, while with HSV-2, there is a much higher rate of recurrence, up to 80%. Recurrences usually occur at the same site, and while the cause of this renewed infection is not completely known, factors such as sunlight, wind, fever, local injury, menstruation, suppression of the immune system and emotional stress are thought to be involved.
HSV infections trigger the body""s immune system, and in healthy people, infections tend to become less severe and less frequent. However, the immune system cannot completely eradicate the virus.
HSV is transmitted by skin-to-skin contact, often by sexual contact and kissing. While those with active sores are much more infectious than those without symptoms, a person does not need to have a visible lesion or ulcer to be infectious. One cannot predict when a person is shedding the virus.
While there is no cure for herpes infections, oral acyclovir has been found to be an effective treatment for patients with first or recurrent episodes of herpes, interfering with the ability of the virus to reproduce itself. While treatment of a primary infection with acyclovir will shorten the duration of lesions and decrease infectiousness, the virus remains in the body for life. Moreover, a small number of patients experience side effects from acyclovir, including headache, nausea, vomiting, rash and impaired kidney function.
A number of topical treatments are known for active lesions, including topical antiviral medicines. Other topical treatments include those disclosed in U.S. Pat. Nos. 4,657,933 and 4,657,934, directed to ethyl ether-based compositions.
Warts are another type of topical viral infection. Warts are caused by viruses in the human papillomavirus (HPV) family. The main types of warts are common warts, found on the elbows, arms and face, molluscum contagiosum, found on the face, back and shoulders, plantar warts, found on the soles of the feet and genital warts, found in the genital area and anus.
Warts may be treated with salicylic acid preparations commonly sold over the counter, or with more sophisticated therapies such as cryotherapy, electrodessication, curretage and laser therapy.
It is therefore an object of the invention to provide a safe and effective treatment for herpes lesions, warts and other topical viral infections with minimal side effects.
To achieve this and other objects, the invention is directed to a method for treatment of topical viral lesions by scrubbing the lesions, and applying thereto an aqueous reagent solution comprising neutral red and free chlorine. The site is then irradiated with ultraviolet light, 40-400 nm wavelength for a period of time effective to destroy the infected cell without causing burns to the skin.